Hello colleagues !

The problem is like that: I have MODBUS Slave communication with CPU 414-4 -H with CP 441-2 to communicate with HONEYWELL DCS system. When I am using only one line there is no problem, but when I connect also the second line for the second CP I can't receive. When they trying to send me command from HMI that I read it with MODBUS it is appear message MODBUS error ! In the attach you can see my Hardware configuration.  

danw

The attachment shows the field slaves labeled as Profibus DP, not Modbus.   So I'm not sure what you have there.

 Yes, because this is the Hardware Configuration. In the Net Pro you can see the Modbus. In this attachment you can see it .

Kaulquappe

Hello Evga,
H-systems do not support redundant serial communication via CP441.

Regards,
Kaulquappe

Then where I can see what kind of CP I can use ?

Kaulquappe

Hello Evga,
does the Honeywell system support Modbus TCP as well? That would be a better solution.

Regards,
Kaulquappe

 This is something that I do not know I need to check and ask. But can you tell me where I can read that this type of redundant CPUs do not support MODBUS SLAVE communication, because I need to convince them.

Kaulquappe

PCS7 system manual section Function and communication modules that can be used in a redundant configuration.

Regards,
Kaulquappe

 This is for different CPU, but I found another manual and seems like you are wright so thank you.